Richard Thaler asks exactly the right question. This from the latest IGM Forum poll of big-name economists, on the effects of taxing income from “capital.”

I’ve been over this multiple times before, but it’s nice to see the thinking validated by a real economist. If you’ve got money, there is no (practicable) alternative to “investing” it. (Those are irony quotes: referring to “buying financial assets,” as opposed to “buying/creating real [fixed] assets,” which is the technical meaning of “investing” in national-account-speak.)

Or actually — there is one alternative to “investing” your money: spending it.

Are the neoclassicals really going to argue that if we tax returns on financial assets at a higher rate — so “investors” have less after-tax income — they’re going to spend more? I don’t think I have to cite sources to prove that they consistently argue exactly the opposite.

But just for grins, let’s say they will spend more. That would be great! They’d increase the volume of private money circulation (P*T, or M*V, your choice) — boosting demand for real goods and services, stimulating production, and goosing GDP.

And if we’re lucky, they’ll use it for investment spending instead of consumption spending. They get to write off those real investment expenditures against their taxes, after all. Not true with consumption expenditures, much less purchases of financial assets.

In which case — this seems kind of obvious when you think about it — taxing “investment” income will increase investment (while reducing the federal deficit). What’s not to like?